http://ideas.live.com/ the official beta-idea website.
It's the official microsoft beta-website, you can join couple of Beta-idea and test parts..
*ps MSN Messenger will stay MSN Messenger, the name will only be changed.. But when you'll download it, it says MSN Messenger.
When you run it, it says: Windows Live Messenger!
So check the website out:
http://ideas.live.com/